300D50

Hello all,

I've engineered myself into a pickle of a corner with my swap project.

Long story short, I forgot to account for clearance of the exhaust ports and the CV jackshaft coming off the transmission.

I can solve this by rotating the engine 20° clockwise (viewed from front cover), bringing the exhaust side up to position the jackshaft under the engine.
Custom oil pan required, but that would be the case anyways.

My concern is the draining of oil back from the irons, since the drain channels are already angled about 45° in the opposite direction. I don't know if this will cause issues that will bite me going down the road, but I suspect it's a bit of an issue.


Anyone have any thoughts on the matter?

Aaron Cake

iTrader: (1)

The rotors do drain through the middle iron as well.

My gut says it won't be an issue.

But I take no responsibility for that answer.

300D50

My gut instinct is that it'll be ok once the scavenging pump is installed, but it still makes me nervous.

If I went with an MSP engine (or just the iron set and rotating assembly), the drains would line up perfectly... Decisions decisions...

peejay

Airplane guys run the engines on their sides. Some run plugs up, some run plugs down.

Is it transverse or longitudinal?

300D50

Transverse mount, mated to a Sentra SE-R Spec V trans, all in a custom tube frame.

I forgot all about the airplane guys...

peejay

You might maybe get drainback issues under hard braking.

You'll definitely want an oil pan baffle to keep the oil from climbing into the front counterweight when in lefthand corners.

Altogether this sounds pretty interesting and can't wait to see more of it.

300D50

Just as some visual aid, here's the rough mockup.

I also found out my engine rotation angle is a liitle bit more than 21°... It's actually going to be 50° instead. I wasn't accounting for the transmission pattern being rotated when I first did my measurements.

I used a 13B model off grabcad, but it's wonkier than ***** himself, so I'm taking stuff I haven't physically measured, or found acurate measurements of elsewhere, with a grain of salt.

Here's the rear view, with the trans level:



A slightly rotated rear view:



Right side view. (Yes I know the model is atrocious...):



Wireframe right side view with only CV, mock adapter plate, and rear iron visible:



I know that the drainage channel is at the wrong angle in the model, I just haven't had time to update it.

peejay

Man, I'd be looking at going the other way, axle between the exhaust and intake. As a bonus, routing the exhaust becomes a lot easier.

300D50

You know, it never occurred to me to see if it would fit between the factory lower intake and exhaust...

Classic case of the tree blocking the forest I think.

300D50

After some measurement with the actual CV shaft, it looks like I'll have to go with a rotated engine.

The spacing is too close for comfort, even with a custom exhaust manifold.

The OMP is also in the way of a straight shot, and I'd like to keep it (paranoia...) to provide decel/no fuel lubrication, in addition to a low level premix.

300D50

Hm. After much head scratching (hello premature bald spot, let me introduce you to your friends), and finding this page, it seems that it is possible to run with only a mild bit of rotation, far less than I thought I'd need.

Tight, but possible.

Goody goody.